A magnetic pulse timer coupled to a semiconductor switch is utilized to activate a power transistor that is connected to an ignition transformer primary winding. Such prior art circuitry is usually dependent upon variations in voltage levels of a DC power source.
An ignition circuit with an improved bipolar activated timer is shown in U.S. Pat. No. 4,377,151 to same applicant. The circuit therein likewise makes use of a timer and its bipolar semiconductor circuit to drive a power transistor connected to the ignition transformer primary winding to activate and deactivate such single power transistor.